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  <title>Document</title>
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<body>
  <script>
    var arr = ['q', 'w', 'q', 'e', 'q', 'r']

    console.log( arr.toString() )
    console.log( arr.join('!') )

    // console.log( arr.splice() )   mdn 

    // function fn() {
    //   var newArr = []

    //   for(var i = 0; i < arr.length; i++) {
    //     // if(newArr.indexOf(arr[i]) === -1) {
    //     //   newArr.push(arr[i])
    //     // }

    //     // if(!newArr.includes(arr[i])) {
    //     //   newArr.push(arr[i])
    //     // }  
    //   }

    //   return newArr
    // }

    // console.log( fn() )
  </script>
</body>
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